Steam-engine



(No Model.) 3 Sheets-Sheet 1.

C. R. ARNOLD. w

, STEAM ENGINE.

Elm-364,627. Patented June 14, 1887.

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Patented June 14,1887;

INVENTOR H M m. T A

STEAM ENGINE,

(No Model.)

O. R. ARNOLD.

' WITNESSES:

(No Model.) 3Sheets -Sheet3.

- G. R. ARNOLD.

STEAM ENGINE.

No. 364,627. Patented June 14', 1887.

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STEAM-ENGINE.

SPECIFICATION forming part of Letters Patent No. 364,627, dated June 14, 1887.

Application filed August 80, 1886. Serial No. 212,170. (No model.)

To all whom, it may concern:

Be it known that I, CRAIG R. ARNoLD, a citizen of the United States, and a resident of Philadelphia, in the State of Pennsylvania,

have invented certain new and useful Steam Engines, tion.

My invention relates to steam-engines of that class wherein two or more cylinders, communicating with a common steam-chest, are located upon and open into a crank case or 'vat, within which the operative parts revolve in a of which the following is a specificalubricating bath.

shaft from the pounding and wear incident t the ordinary operation of the piston.

It also consists in jointing the connectingrod to the piston and to the crank respectively, so as to make the line of motion of the con; necti ngrod on the downward or working stroke as nearly as possible perpendicular to the crank at the point of greatest thrust-that is to say, when the crank is in its extreme horizontal position.

It also consists in inclining the upper face of the piston-head so as to relieve the tendency of the piston to hang or buckle, due to the eccentric jointing of the connecting-rod.

It also consists in providing the engine with a hollow connecting-rod and suitable devices to force the lubricating material up through such connecting-rod to the wrist-pin for the purpose of lubricating the same.

It also consists in an automatic float whereby the lubricating fluid in the vatis maintained at a constant level.

It also consists in carrying the steam-chest somewhat above the top of the cylinders in order to secure the steam-ports to the two cylinders of equal length.

It also consists in providing self-adjusting bearings for the crankshaft, whereby said shaft may be easily lined up without resorting to the ordinary methods;

It further consists in certain details of construction more particularly described herein, and pointed out in the claims.

In the accompanying drawings, Figure l is a longitudinal vertical central section showing parts in' elevation. Fig. 2 is a transverse vertical section through one of the cylinders and connecting-rod. Fig. 3 is a diagrammatic rep resentation of the connecting-rod in its various positions- Fig. 4 is a detail view of one of the features of my invention. Fig. 5 is a transverse vertical section showing the float in elevation with other parts of the machine removed. Fig. 6 is a horizontal section on the line 00 :0, Fig.

A and B are cylinders located upon the crank-case O, with their lower ends open thereto. The connecting-rods a b are joined at one end to the pistons E F, and at the other end to the cranks G H, oppositely placed upon the crank-shaft I--that is to say, making an angle of one hundred and eighty degrees with each other.

The steam-chest L, located between the cylinders and rising some distance above the same, is provided with the ordinary portsleading into and out of said cylinders. By carrying the steam-chest some distance above the cylinders, I am enabled to make the steamports 0 d symmetrical in their relation to the cylinders and of equal length, as shown.

The main or distribution valve V is recip rocated in the stea1n;cl1est,by means of the I ward stroke, the steam is exhausted through i the same ports, and is led through suitable passages in the main valve to the exhaust- IOO chamber T. The exhaust-chambercommunicates with an annular chamber, h, surrounding the steam-chest, by means of the ports 9 10. The cylinders A B are also cored out to form the annular chambers ll 12, communieating with the annular chamber h, surrounding the steam-chest. By means of this construction the exhaust-steam is permitted to circulate around the steam-chest and the cylinders, thereby serving to steam-jacket these -parts and maintain the temperature of the same, and at the same time to reduce the tem perature of the exhaust-steam. The exhauststeam escapes from the annular chamber h through the exhaust-ports 23 or 24,either of which may be utilized for that purpose, as may be convenient. The steam-chest is closed in at some point below the ports 9 10 by the sta tionary head 14, forming a close joint with the shoulder 15, which supports the gland-bearing 1G. The gland-bearing makes a steam-ti h t joint with the pitman in the usual manner.

It will be apparent that by replacing the auxiliary or moving piston, which is ordinarily employed in this class of machines, by the stationary head, as described, the workingparts will be relieved of the pounding or hammering due to the irregular action of the exhaust-steam upon the auxiliary piston, tending as it does to accelerate its downward movement and to retard its upward movement.

My device for cushioning the piston on its downward or working stroke is as follows: The pistons and cylinders are made differential in diameter. The piston-head 0 fits and slides in the enlarged portion of the cylinder f, and the piston-slide g g fits and slides in the reduced portion of the cylinder 7.2 k, thereby forming an annular chamber, L, around the pistoirslide and beneath the pistmrhead.

Ports M M lead through the cylinder-walls from thc-exhaustchamber of the steam chest and open into the annular chamber L in such position as to just clear the top of the piston when it is at the limit of its downward travel.

The operation of this part of my machine is as follows: In the position shown in Fig. 1 the piston E has completed its downward stroke and the piston F is in position to begin its downward stroke. The steam being admitted through the port It, the piston F is forced to the bottom of the cylinder, thereby forcing up the piston E into its initial position, and any water of condensation that may have found its way into the cylinder F escapes through the port in. As the piston E rises the exhauststeam is drawn through the port M into the annular chamber L. Upon the downward stroke of the piston the piston-acad closes the port M, and the steam left in the annular chamber is compressed by the piston-hcad upon its further descent and forms a steam-cushion, which takes up the pressure of the descending piston and communicates it to the frame of the engine. The operation is repeated with each of the cylinders in the same manner. A pop-valve, 25, located in the ports M M, allows the steam to escape from the annular chamber L when it has reached a predetermined pressure. I also relieve the wear upon the bearings of the crank-shaft, and at the same time increase the efficiency of the ma chine, by the peculiar arrangement of the pis-i ton, connecting-rod, and crank, which I will now describe.

The connecting-rods a Z: are jointed to the crank-pin of the crank in the ordinary manner, as shown. At the other end, however, they are jointed to the piston eccentrically, the wrist-pin a being located to one side of the center of the piston, and as nearly as possible in line with the crank-pin a when the latter is at its extreme horizontal position. This is the position of the crank when the force of the descending piston is most advantageously applied; and by locating the wrist-pin directly over the crank-pin I am enabled to increase this advantage by applying the downward motion of the piston in a nearly vertical direction upon the crank, so that very little of the downward force is expended upon the bearings. The wrist-pin is located sufficiently far, however, from the side of the cylinder, so that it will not be necessary to enlarge the lower open end of the cylinder to permit of the necessary movements of the connecting-rods.

The disadvantageous position of the connceting rods upon the upstroke is unimportant in a single-acting machine of this description. It will be seen,upon inspect-ion of Fig. 3,that during the downward stroke, when alone work is being performed, theline of motion passing through the wrist-pin and the crank-pin is substantially vertical in all positions, and that therefore no advantage is lost from the eccentric location of the wrist-pin in any of the working positions of the engine.

To compensate for the tendency of the pistons to hang or buckle in the cylinder, due to the eccentric location of the wrist-pin, I incline the upper face of the piston-head to the line of pressure in the manner shown, so as to obtain a resultant pressure in a horizontal direction.

It will be understood,of course, that thcaugle ofinclination of the upper surface of the pistonhead will depend upon the eccentricity of the wrist-pin.

The devices for automatically maintaining a proper depth of lubricating fluid in the crank case or vat are as follows: A float, S, located upon the long arm of thelevcr s, rises and falls with the rise and fall of the liquid in the vat. To the short arm of the levers are attached the ends of the bell-crank lovers 1' I, which control, respectively, the valve E, which admits the water of condensation from the exhaust-chamber, and the valve E which allows the water at the bottom of the mixture in the vat to flow off.

The operation of the device is as follows: lVhcn from any cause thelevel ofthe mixturein the vat falls,thciloatS falls with it and thereby opens the valve E, through its connection with the bell-crank lever 1*, thereby permitting the water of condensation from the exhaust-chamber to flow into the vat. 011 the other hand, when the level of the lubricating fluid rises,

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the float, through its connection with the bellcrank lever t, opens the valve at the bottom, thereby allowing the water, which naturally sinks to the bottom of the mixture, to escape. The parts are so adjusted that this action of Ithe {loat will keep the liquid at the proper eve The connectingrodsa b are hollow,as shown in Figs. 2 and 4, and are provided at their lower ends with openings at of reduced diameter. A ball-valve, o, normally closes this opening. The upward travel of'this ball is limited by the set-screw to. As the crank and the lower end of the connectingrod dip into the lubricating-vat the commingled oil and water are forced into the lower end of thehol' low connecting-rod through the aperture a. As the connecting-rod rises from the bath the ball -valve falls and prevents the lubricant from escaping. By a repetition of this pro .cess the lubricating fluid gradually rises in the hollow connecting-rod untilit reaches the wrist-pin, wl.tich is thereby thoroughly lubricated.

' The'crank-shaft I isprovided with tapering bearing-surfaces 1 1. These bearing-surfaces pass into and are automatically centered or lined up by correspondingly tapered bushings, 2 2. The bearing-surface proper, indicated at 2, is a linin g or sleeve of Babbitt metal cast integral with the inclosing-bushi-ng 4,and tapered on its interior surface to correspond with the taper-of the shaft. The bushing 4 is screw-threaded exteriorly and screws into bracket 5. The bearings 2 4 are provided. with a square end, 8, to which a wrench may be applied. the outer end of the bracket 5, protect the parts from dust and other impurities of the air.

The operation of the devices is as follows: The wrench being applied to the square head 8 of thebearing 2 4, a forward and circular movement is given to the bearing-surface proper, 2, which is ,thereby caused not only to advance upon the tapered shaft so as to take up the wear in a longitudinal direction, but 1S also caused to rotate upon the same in a CIICUIZIIHGIXECIIOD, thereby bringing a new sur face into contact circumferentially. A setscrew, 26, passing through the bracket 5,takes into the screw-threads 011 the part 4 and prevent's the same from moving when once ad justed.

A channel, 7, supplies the bearings with the lubricant from the vat. A set-screw, 26, prevents the bearings from turning with the shaft. As wear takes place the sleeve is turned by a wrench and a new bearingsurface ex posed, which is caused by this arrangement to automatically center itself upon the shaft.

I am aware of the Patents Nos. 303,083 and 340,022 granted to H. H. Westinghouse, and I make no claim to the construct-ion therein shown and described; but

What I do claim as my invention is- 1. In a single-acting engine, a cylinder hav- Inclosing-caps 6, screwing into ing a steamcushion chamber alternately communicating with the steanrchest by a port which just clears the top of the piston in its lowest position and closed by the piston, as and for the purpose described.

2. The combination, with a steamchest of a single-acting enginc, of apiston and acylinder having a steam-cushion chamber formed by the walls of the piston and cylinder and communicatin g with said steanrchest upon the upstroke of the piston by aport which just clears the topvof the piston in its lowest position, as and for the purpose described.

3. In a direct-acting engine, the combination of a steam-chest, a differential cylinder, a differential piston, an annular steam-cushion chamber formed thereby, and a port from said steam-chest opening into such chamber upon the upstroke of said piston, as and for the purpose set forth.

4. In a single acting engine wherein the crank-shaft is in the plane of the cylinderaxis, a connecting-rod so jointed to the moving parts that its line of motion upon the down or working stroke will be substantially perpendicular to the crank in its horizontal position, as and for the purpose described.

5. In a single-acting engine wherein the crankshaft is in the plane of the cylinderaxis, the combination of a piston, a crank, and a connectingrod so jointed to said piston and crank that the line of motion upon the down or working stroke will be substantially perpendicular to said crank in its horizontal position, as and for the purpose described.

6. In a singleacting engine, the combination of a piston, a crank, and a connectingrod jointed ececntricallyto the piston in such manner that its line of motion on the downstroke will be substantially perpendicular to such crank in its horizontal position.

' 7. In a single-acting engine, the combination of a piston,\ a crank, and a connectingrod extending from the crank-pin to a wristpin on the underlside of said piston and to one side of the centerthereof, whereby the line of motion of the connecting-rod on its downstroke will be substantially perpendicular to the crank in its horizontal position,-as and for the purpose described.

8. In a direct-acting engine, a piston eccentrically jointed to its conneetingrod and the upper face of which is inclined to the line of its movement, as and for the purpose de scribed.

' 9. In a single-acting engine, the combination of a cylinder, a piston, a crank, and a connectingrod jointed eccentrically to said piston, the upper face of said piston being inclined to the line of pressure, as and for the purpose described.

10. The combination, with the moving parts of a steam-engine, of a hollow connecting-rod,

a crank case or vat containing a lubricating liquid, into which such eonneetingrod dips, whereby such lubricant is introduced into the interior of such connecting-rod, and means for maintaining the level of the lubricating liquid in such vat, and a float in such vat controlling valves for admission of water and escape of the mixture, as and for the purpose described.

11. The combination, with the moving parts of a steam-engine, of a hollow connecting-rod provided at its lower end with a valved opening, a vat of lubricating material into which such connecting-rod dips at each revolution, whereby such lubricating fluid is forced up through said connecting-rod to the upper joint, and means for maintaining the level of the lubricating liquid in such vat, and a float in suchvat controlling valves for admission of water and escape of the mixture, as and for the purpose described.

12. In a single-acting engine, the combination of a crank-ease containing a lubricating mixture, an open-ended cylinder thereon, a piston, a crankshaft and crank, ahollow connecting-rod dipping into such mixture at each revolution of the crank, whereby the lubricating material enters such connecting-rod, and means for maintaining the-level ot the lubricating liquid in such vat, and a float in such vat controlling valves for admission of water and escape of the mixture, as and for the purpose described.

13. In a single-acting engine, the combina tion of a crank-case containing a lubricating mixture, an open-ended cylinder thereon, a piston, a crankshaft and crank, a hollow connecting-rod provided at its lower end with a valved opening, whereby the lubricating mixture is forced up through such eonnectingrod, and means for maintaining the level of the lubricating liquid in such vat, and a float in such vat controlling valves for admission of water and escape of the mixture, as and for the purpose described.

14:. In a single-acting engine, the combination, with the working partsthereofiofa crankcase containing a lubricating mixture, a float therein, a valve for the escape of the mixture, a valve for the admission of water, and means whereby these valves are automatically controlled by said float, as and for the purpose described.

15. In a single-acting engine, the combination,with the working parts thereofiofa crankcase containing a lubricating mixture, a float therein, a valve for the escape of the water, and a valve for the admission of water, and bell-crank levers controlling said valves and actuated by said float, as and for the purpose described.

16. In a single-acting engine, the combination of two cylinders provided with annular steam-ehambers,a steam-chest common to said cylinders and provided with suitable entrance and exit ports, and an exhaustchamber at one end communicating with the annular steamchambers of said cylinders, as and for the purpose described.

17. In a single-acting engine, the combination of two cylinders provided with annular steam-chambers, a steam-chest common to said cylinders and surrounded by an I annular steam-chamber and provided with an exhaustchamber at one end communicating with the annular-chamber of the steam chest and the annular-chambers of the cylinders, .as and for the purpose described.

18. In a single-acting engine, the combina' tion, with a crank case or vat, of two cylinders located thereon and opening therein, a steamchest located between said cylinders, annular steam-chambers surrounding said cylinders and said steam-chest, and an exhaust-chamber at one end of said steam-chest communicating with said annular chambers and closed on the end adjoining the crank-ease by a stationary head, as and for the purpose described.

19. The combination, with a crank-shaftprovided with tapered bearing-surtaces, of correspondi ugly-tapered bearings surrounding such surfaces and screwing into a bracket, 5, inclosing-caps attached to the end of said bracket, and retaining-screws passing through said bracket, as and for the purpose set forth.

Signed at Philadelphia, in the county of Philadelphia and State of Pennsylvania, this 25th day of August, A. D. 1886.

CRAIG R. ARNOLD.

Witnesses:

Framers S. BROWN, HENRY A. MoMURRow. 

